Hello all. I have a significant pool leak. I canít locate the problem on my own and could do with some advice on what should be my next steps.
Pool was built in 2004 and itís a vinyl liner design. It has had construction based issues with subsidence. About 3 years after it was constructed it was repaired on one side due to subsidence under the pool base and around and behind the wall on side of the pool near skimmer. This was repaired by the original builder with some shoring up with pit gravel under the pool and behind the wall resulting in new concrete decking on that side of the pool. This seems solid. The builder and I concluded after the last repair that that one of the main causes of the subsidence was that when the house was built in late 80ís the builders buried tree stumps from the property in the back yard. When the hole for pool was dug out I strongly suspect that they did not get out all of these stumps and logs out and pool was constructed above some of them. My suspicion is that these are slowly rotting and causing earth movement.
The reason I give the background is that at this time the pool is showing signs of more movement in two places. One near the steps which have sunk about Ĺ inch causing cracks in the brick coping and at also at the far end the brick coping has moved about ľ inch away from the concrete decking behind it. I know that the dirt from under the steps has moved as it sounds hollow when knocking on them. These issues I am certain will need addressing at some point which I was considering next spring. However over the last few weeks I became aware of a leak which to me is highly likely to be related to the above issues, but so far have not determined where. (I can provide pictures if it helps!)
A few weeks ago I suspected losing water but it was difficult to pinpoint as we were having daily storms that could add Ĺ inch to 2 inches of water with one downpour. This last week I there has been no rain. I marked the water level each day and could see it drop approximately ľ inch per day. At a 24000 pool which I estimate is an average of 50 inches deep Ė I calculate this at losing 480 gallons per day!
I was strongly suspicious of the plumbing and/or the skimmer. I have now allowed the pool level to drop just below the skimmer. The skimmer is now dry AND the leaking has stopped. Obviously this makes me highly suspicious of the plumbing!
I have also spent quite some time in the water when it was very still examining the liner last weekend. I used some food dye in the water around some suspicious areas like the pool steps. I cannot see an obvious leak in the liner. I paid particular attention to this around the seals of the steps where they meet the pool.
So what should be my next steps?
I believe I should contract a pool builder/repair company and I understand that they have the ability to do a test of the plumbing to see if has a leak. Is this correct?
What will this tell me? Simply there is a leak in plumbing or can it narrow down the location?
Would you recommend this? What should I expect the cost to be for such a test and what should I learn from this?
BTW thanks to all who contribute on this forum Ė I have found it invaluable since joining earlier this year